Magnetic-stripe cards are often used as credit cards, debit cards, and Automated Teller Machine (ATM) cards. These magnetic-stripe cards are used with transaction machines, such as ATMs, gas station pumps, and point-of-sale (POS) machines (for example, at a grocery store, drug store, or department store), any of which include a card reader that reads account information from the card. The magnetic-stripe cards also may be used to gain access to a transaction machine. For example, some ATMs are enclosed in a vestibule, and entry to the vestibule is provided through a locked door that may be unlocked in response to a user inserting a magnetic-stripe card in a card reader associated with the door. The card readers usually are one of three types: dip readers, swipe readers, and motorized readers. To use a dip reader, a card holder inserts the magnetic-stripe card into a slot and then immediately withdraws the card. The dip reader includes a scanning head in the slot that reads the account information on the magnetic stripe of the magnetic-stripe card as the card holder inserts and removes the card. To use a swipe reader, a card holder slides the magnetic-stripe card through a slot. The swipe reader includes a scanning head in the slot that reads the account information on the magnetic stripe of the magnetic-stripe card as the card is passed through the slot. To use a motorized reader, a card holder inserts the card into a slot. In the slot, motors and grabbing devices take hold of the magnetic-stripe card and pull the card into an internal portion of the card reader. The card reader then moves the card such that its magnetic stripe passes over a scanning head that reads the card. The motorized reader usually holds the card until the card holder has completed a transaction. Often times, in addition to passing a magnetic-stripe card through a card reader, a card holder also must enter a code (often referred to as a “personal identification number” or “PIN”) into a keypad on the transaction machine.
Magnetic-stripe card readers are susceptible to “skimming,” in which the account information on a magnetic-stripe card and the PIN entered onto a keypad are secretly recorded for later use by a criminal (called a “skimmer” herein). The skimmer wants the mold to be unnoticed by the card holder at the transaction device. The mold may be an exact replica of the exterior surface of the card reader that fits over the card reader. Alternatively, the mold may have a generic look. In either instance, the skimmer wants the mold to be as small as possible to minimize chances that a card holder (or any other person) recognizes that the mold is on the transaction device. The mold includes a scanning head that reads the account information off of the magnetic stripe of the magnetic-stripe card. The mold also includes a memory device coupled to the scanning head that stores the account information for later retrieval by the skimmer. Importantly, the mold must not interfere with the card holder's ability to use the card reader. If the card holder is not able to insert a magnetic-stripe card and have it read by the transaction machine, then the user likely will not attempt to enter the PIN and may be alerted to the possibility of a skimming device being used. For this additional reason, a skimming device mold must be as small as possible so that it does not interfere with a card user's use of a magnetic-stripe card in a transaction machine.
The skimmer also discretely places a small camera on or nearby the transaction machine that captures images of the keypad of the transaction machine so that the skimmer can get both the account information from the magnetic-stripe card and also the PIN associated with the card.